Molded plastic container secondary operations machine

ABSTRACT

A method and apparatus is provided for performing secondary operations on plastic containers including deflashing, machining, leak detecting and dimension checking. The assemblies for performing these secondary operations are synchronized and designed to enable sequential operations to each of a continuing succession of containers to enable more and faster operations than in the past. A transfer mechanism indexes the containers between operation stations. Defective containers are rejected as the containers emerge from the processing apparatus.

I United States Patent 1 1 11 11 3,791,245 Eggert Feb. 12, 1974 MOLDEDPLASTIC CONTAINER 3,464,084 9/1969 Thompson 83/914 x SECONDARYOPERATIONS MACHINE 5] Inventor! Noel gg Toledo, Ohio PrimaryExaminer-WillieG. Abercrombie gne Owens-Illinoislnc Toledo Attorney,Agent, or M. Rice; J. Holler 22 Filed: Nov. 28, 1972 [21] Appl. No.:310,176 [57] ABSTRACT [62] Divisim of 93,069 1.970, secondary operationson plastic containers including deflashing, machining, leak detectingand dimension checkin The assemblies for performin these secon- 52 us.Cl 83/370, 83/380, 33/390, dary opfirafions are Synchronized anddisigned to em 83/914 425/806 able sequential operations to each of acontinuing suc- [51] Int. Cl B26d 5/04, B26d 5/28 cession of containersto enable more and faster opera [58] meld 0f seal-chm" 83/365 390; tionsthan in the past. A transfer mechanism indexes 425/806 the containersbetween operation stations. Defective containers are rejected as thecontainers emerge from [56] References the processing apparatus.

UNITED STATES PATENTS 3,377,899 4/1968 Wolford 83/914 X 14 Claims, 37Drawing Figures Related US. Application Data CONTAINER FLOW A method andapparatus is provided for performing PATENIEU FEB 12 I974 sum 02oF 1-7PATENTEDFEB 12 B74 SHEET OBUF 17 PATENTEDFEBIZIHM 3.791.245 SHEET UHU'F17 PATENTEDFEB 12 1914 saw 050; 17

PATENTEDFEB 12 1914 SHEET 08 0F 17 FIG. 20

PATENTED FEB 12 I974 sum new 17 m 90- RilEASE BULB FIG.23

FIG. 2i

FIG. 22

FIG.24

PATENTEDFEB 12 m4 379L245 SHEET 1 HF 17 JCT1 PR2 +60 PR POWER 6 SCI-BSUPPLY AIR COMPRESSION AND/OR STORAGE PATENTED'FEB 12 m4 .3. 791. 245

sum ISUF 17 PTS PRESSURE TEST SENSOR CD7"\ [LEADS CD8 BRK LEAK DETECTORMOLDED PLASTIC CONTAINER SECONDARY OPERATIONS MACHINE CROSS REFERENCE TORELATED APPLICATION This is a division of application Ser. No. 93,069,filed Nov. 25, 1970, now US. Pat. No. 3,716,910.

BACKGROUND OF THE INVENTION For convenience, certain terms employed inthe specification are defined as follows.

The term flash" refers to a finlike web which projects from the surfaceof the article. Flash is formed in the molding operation by materialwhich is caught between the closing mold halves or forced between themold half faces during the molding operation.

The term moil" refers to the plastic left from the original gob afterthe container has been blown in the mold and severed from the supply. Inthe present case the moil extends upwardly from the finish neck portionof the bottle.

While the invention will be described specifically with respect toperforming secondary operations on a molded plastic bottle having anintegrally molded handle, it will become apparent from the descriptionthat the invention is applicable to other types of molded articles. Themolded plastic bottle having a handle has been chosen as a specificexample since this particular article presents a wide variety ofproblems in performing secondary operations thereon. I

In the molding of plastic bottles of the foregoing type, the neck orfinish of the bottle is first injection molded and a tubular parison isformed, or the tubular parison is formed and the neck or finish is blownin the molds. The parison is then positioned in operative alignment witha pair of blow mold halves which are then closed upon the parison. Theinterior of the tubular parison is then pressurized to expand theparison into contact with the mold walls. In the formation of handledbottles, the tubular parison is initially expanded prior to the closingof the mold to make sure that the handle portion of the mold will closeupon a portion of the parison. This inherently requires that the.closing mold halves grip between them some of the plastic material ofthe parison, thereby resulting in a web of plastic material within thehandle opening at the conclusion of the molding process. Additionally,as the mold closes, a certainamount of the parison is caught between theclosing mold faces in the region of the shoulder, thus resulting inprojecting-fins on the shoulder of the completed article. The projectingfins and the web within the handle openingare referred to belowgenerally as flash.

In the forming of plastic bottles, problems are frequently encounteredby the presence of minute pin holes in the bottles. Although not readilydiscernible to the eye, the presence of such pin holes is reason forrejecting the bottle.

Accordingly, it is necessary that plastic bottles be tested to'determinewhether suchbottles have pin holes which would present problemsifithebottle were used for packaging goods. The bottles varecustomarilytested by introducing ttherein .fluid pressure from an outside sourceand waitinga period of time to see'whether such pressure islostthroughpin holescontained in the bottle. The plastic containers havealso had to be individually dimensionally checked,particularly to seewhether the finished height of the container was within a desiredtolerance. This is necessary because the containers may be passedthrough automatic container filling machines, packing machines, etc.,and a container that is too short or too tall may cause an automaticmachine to malfunction.

Various machining operations are also performed on plastic containers toface, ream, chamfer, or otherwise finish particular portions of thecontainers.

Individual machines have been designed to individually perform thesecondary operations discussed, some of which have been operatedrelatively successfully. However, there are container handling andorienting problems when the containers are moved from machine to machinefor each operation. Further, individual machine operations arerelatively slow because the containers must be handled and reorientedbetween machines and because the operations of one machine were nottimed with respect to the operations of the next machine. Moreover,individual machines for each operation are more expensive, occupy morevaluable floor space, require more operator attention, and cause morecontrol problems.

In addition, since the plastic used in manufacturing some containerstends to change dimensionally in response to temperature changes, e.g.,after it cools on emerging from the mold, it is important that seconaryoperations be performed quickly after molding, and/or rapidly withrespect to each other, so that the secondary operations can be performedon the container while it is in a particular dimensional range to enablemore accurate results from the secondary operations without adjustingindividual machines.

Accordingly, it is an object of this invention to provide novelapparatus for performing several secondary operations on plasticcontainers, the operations being sequentially performed in the apparatuswhich synchronizes the operations with respect to each othermechanically, pneumatically, and electrically.

It is a further object of this invention to provide improved deflasher,machining, leak detecting and dimension checking assemblies which arenovel and useful separately, or which may be combined as shown.

It is a still further object to provide an improved transfer mechanismfor moving or indexing containers or other objects between stations.

It is another object of this invention to provide an improved method ofand apparatus for performing secondary operations on molded plasticarticles.

Other objects, advantages and features of this invention will becomeapparent when the following description is taken in conjunction with theaccompanying drawings, in which:

FIG. 1 is a side elevational view of apparatus embodying the teachingsof this invention taken from the left side of container flow from theloading station through the apparatus;

FIG. 2 is an end elevational view taken from the downstream side oftheapparatus illustrated in FIG. 1;

FIG. 3 is a bottom view of means for determining the index position ofthe transfer mechanism;

FIG. 4 is a side elevational view of the apparatus illustrated in FIG.3;

FIG. 5 is a plan view of the index control portion of the transfermechanism;

FIG. 6 is a side elevational view of the'apparatus illustrated in FIG.5, partially in section taken along lines VI-Vl in FIG.

FIG. 7 is a side elevational view of the transfer mechanism emphasizingthe clamp rails and apparatus for moving same;

FIG. 8 is a plan view, partially in section, of the apparatusillustrated in FIG. 7;

FIG. 9 is a sectional view of the apparatus illustrated in FIG. 7 takenalong lines IXIX of FIG. 7;

FIG. 10 is a plan view illustrating escapement apparatus located betweenthe loading and orientation stations;

FIG. 11 is a side elevational view of the apparatus illustrated in FIG.10;

FIG. 12 is an end elevational view partially in section, of theapparatus illustrated in FIG. 11, looking upstream toward the loadingstation;

FIG. 13 is a side elevational view of the deflasher assembly taken fromthe same side of the apparatus as illustrated in FIG. 1;

FIG. 14 is cross-sectional view of the deflasher assembly illustrated inFIG. 13, taken along lines XIX- -XIX of FIG. 13;

FIG. 15 is a cross-sectional view of the deflasher assembly illustratedin FIG. 14, taken along lines XV-XV of FIG. 14;

FIG. 16 is a cross-sectional view of the deflasher assembly illustratedin FIG. 14, taken along lines XVI- XVI of FIG. 14;

FIG. 17 is a cross-sectional view of the deflasher assembly illustratedin FIG. 14, taken along lines XVII- XVIl of FIG. 14;

FIG. 18 is a side elevational view of a stabilizer assembly at an idlestation;

FIG. 19 is a plan view of the facer and leak detector drive carrierassembly;

FIG. 20 is a cross-sectional view of a portion of the apparatusillustrated in FIG. 19, taken along lines XX-XX of FIG. 19;

FIG. 21 is an enlarged view of the facing spindle feed cam and includesa graphic representation of its cyclic operation;

FIG. 22 is an enlarged view of the leak detector assembly feed cam andincludes a graphic representation of its cyclic operation;

FIG. 23 is an enlarged view of the bellows compressing cam and includesa graphic representation of its cyclic operation;

FIG. 24 is a plan view of the facer assembly;

FIG. 25 is an end elevational view of the facer assembly lookingdownstream of the container flow therethrough;

FIG. 26 is a bottom view of the facer assembly illustrated in FIG. 25;

FIG. 27 is a side elevational view of the facer assembly taken from theleft side of the machine;

FIG. 28 is a cross-sectional view of the facer assembly in FIG. 24,taken along lines XXVIII-XXVIII of FIG. 24;

FIG. 29 is a side elevational view of the leak detector and dimensionchecking assembly, partially in section, taken from the left side of themachine;

FIG. 30 is an end elevational view of the assembly illustrated in FIG.29, partially in section, looking upstream toward the container flow;

FIG. 31 is a bottom view of the assembly illustrated in FIG. 30;

FIG. 32 is a plan view of the eject mechanism and the unload station;

FIG. 33 is a side elevational view of the apparatus of FIG. 32 takenfrom the left side of the machine;

FIG. 34 is a schematic diagram of the air supply and air control circuitfor the deflasher and facing stations;

FIG. 35 is a schematic diagram of the air supply and air control circuitfor the leak detecting and dimension checking station;

FIG. 36 is a schematic diagram of a first part of the electrical controlcircuit for the apparatus herein; and

FIG. 37 is a schematic diagram of a second part of the electricalcontrol circuit of this invention.

SUMMARY OF THE INVENTION Referring to the drawings there is illustratedin FIG. 1 a side elevational view taken from the left of the center lineof container flow through the apparatus and in FIG. 2 an end elevationalview taken from a downstream side of FIG. 1, a general assembly layoutof a machine 30 incorporating the teachings of this invention.

The machine 30 is designed to accept blown plastic containers 280 andperform secondary operations of deflashing, facing or other machiningwork, dimensional checking, and leak detection. The containers 280 arethen deposited on an unloading conveyor or other removal means.Containers not within the dimensional or leak detection tolerances areejected from the unloading conveyor and the remaining containers areconveyed to packing, filling, or other container use areas.

To perform these operations the preferred embodiment of the machine 30includes nine in-line stations which are noted in FIG. 1 as load station31, orientation station 32, idle station 33, deflash station 34, idlestation 35, facing or other machining station 36, idle station 37, leakdetection and dimensional checking station 38, and unload station 39.The assembly and mechanism at each station will be described in detailhereinafter. However, to provide an initial understanding of the machinefunctions, the operations at each station are set forth briefly here.

Containers 280 are delivered to load station 31 by an endless beltconveyor 260. An escapement mechansim blocks free entry of containers280 into the load station causing the containers to accumulate in acolumn on conveyor 2 60. The escapement mechanism releases one containerat a time to the load station in synchronization with the operation ofan in-line transfer mechanism designated generally at 118 which moves orindexes individual containers from station to station. A containerdetection unit monitors the presence or absence of containers availableat the load station and generates a signal in response to the lack ofcontainers which may be utilized to shut down completely or temporarilyhalt the operation of the entire machine until one or more containersare again available at the load station.

The containers are properly oriented at the orientation station 32 forsubsequent operations at succeeding stations. No specific orientingmechanism is described herein but an orienting means similar to thatdisclosed in US. Pat. No. 3,377,899, issued Apr. 16, 1968, may

1. Apparatus for removing flash and the like from a molded object at adeflashing station comprising, a. a knife platen carrier on one side ofsaid station, b. means for advancing said knife platen carrier to aflash severing position in response to an object being at said stationfor deflashing and for withdrawing said knife platen carrier to itsstarting position after the flash is severed from the object, c. a firstnest platen carrier located on said one side of said station, d. asecond nest platen carrier located on the other side of said station. e.means responsive to the advance of said knife platen carrier foradvancing at least one of said nest platen carriers toward the other ofsaid nest platen carriers to a position which nests and holds the objectfor flash severing before said knife platen carrier reaches a flashengaging position, and f. means responsive to the withdrawal of saidknife platen carrier from an engagement position with said object forwithdrawing said one nest platen carrier away from the other of saidnest platen carriers to release the nested object.
 2. Apparatus asdefined in claim 1 in which said means responsive to the advance of saidknife platen carrier includes means for yieldingly biasing one of saidnest platen carriers toward said station to maintain an inwardly facingportion of one of said nest platen carriers urged against an outwardlyfacing portion of said knife platen carrier until a nesting portion isreached.
 3. Apparatus as defined in claim 2 in which said nest platencarrier yieldingly biasing means is mounted on said knife platen carrierso that, after said one nest platen carrier reaches nesting position,the continued advance of said knife platen carrier increases the biasingforce to hold said one nest platen carrier more firmly in nestingposition.
 4. Apparatus as definined in claim 3 which further includesmeans for reducing the biasing force of said yieldingly biasing means inresponse to the start of withdrawal of said knife platen carrier toreduce the increased force from said yieldingly biasing means which isnow pushing on said knife platen carrier during withdrawal of said knifeplaten carrier.
 5. Apparatus as defined in claim 3 in which saidyieldingly biasing means includes an air spring and which furtherincludes means for reducing air pressure in said air spring in responseto the start of withdrwal of said knife platen carrier to reduce theforce of said air spring pushing on said knife platen carrier duringwithdrawl of said knife platen carrier.
 6. Apparatus as defined in claim5 in which said air spring pressure is vented to the atmosphere inresponse to the sTart of withdrawal of said knife platen carrier, and inwhich said yieldingly biasing means further includes auxiliary springmeans positioned between said knife platen carrier and said one nestplaten carrier, said auxiliary spring means having a spring force whichis sufficient to hold said one nest platen carrier in the nestingposition until said knife platen carrier has withdrawn from anengagement with said object.
 7. Apparatus as defined in claim 3 in whichsaid means responsive to the withdrawal of said knife platen carrierincludes said outwardly facing portion of said knife platen carrier inregistration with said inwardly facing portion of said one nest platencarrier, so that withdrawal of said knife platen carrier causes contactbetween said outwardly and inwardly facing portions after said knifeplaten has reached a disengagement position and pushes said one nestplaten carrier outwardly.
 8. Apparatus as defined in claim 1 whichfurther includes a. means for causing the reaching of a nesting positionby said nest platen carriers, and b. means responsive to said nestingsensing means for generating a no-nesting signal if said nest platencarriers do not attain a satisfactory nesting position.
 9. Apparatus asdefined in claim 8 which further includes means responsive to saidnesting sensing means for interrupting operation of the apparatus ifsaid nest platen carriers do not attain a satisfactory nesting position.10. Apparatus as defined in claim 1 which further includes a. means forsensing a movement out of nesting position by said nest platen carriersafter an initial nesting position is satisfactorily attained and beforesaid knife platen carrier withdraws to a position of disengagement, andb. means responsive to said nesting movement sensing means forgenerating a nesting movement signal if such movement is detected. 11.Apparatus as defined in claim 10 which further includes means responsiveto said nesting movement sensing means for interruptng operation of theapparatus if such movement is detected.
 12. Apparatus as defined inclaim 1 in which said means for advancing and withdrawing said knifeplaten carrier includes a. rotating drive means, and b. connecting meansbetween said rotary drive means and said knife platen carrier fortranslating the rotary motion of said drive means into reciprocal linearmotion for advancing and withdrawing said knife platen carrier. 13.Apparatus as defined in claim 12 in which said rotating drive meansincludes a one revolution output mechanism energizable to provide a onerevolution output which will complete a single cycle of advance andwthdrawal of said knife platen carrier.
 14. Apparatus as defined inclaim 1 in which said first nest platen carrier includes a first rackmeans and in which said second nest platen carrier includes a secondrack means, and which further includes pinion gear means mounted on afixed pivot, the teeth of said pinion gear means being meshed with teethof said first and second rack means so that the advance and withdrawalof one nest platen carrier will cause a similar advance and withdrawalof the other nest platen carrier thereby synchronizing the nest platencarriers and requiring advancing and withdrawing means for only one ofsaid nest platen carriers.